kolchos = [101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199,
           211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311, 313, 317, 331,
           337, 347, 349, 353, 359, 367, 373, 379, 383, 389, 397, 401, 409, 419, 421, 431, 433, 439, 443, 449, 457,
           461, 463, 467, 479, 487, 491, 499, 503, 509, 521, 523, 541, 547, 557, 563, 569, 571, 577, 587, 593, 599,
           601, 607, 613, 617, 619, 631, 641, 643, 647, 653, 659, 661, 673, 677, 683, 691, 701, 709, 719, 727, 733,
           739, 743, 751, 757, 761, 769, 773, 787, 797, 809, 811, 821, 823, 827, 829, 839, 853, 857, 859, 863, 877,
           881, 883, 887, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977, 983, 991, 997]
a = input()
ans = []
s = a.split()
if len(s) >= 3:
    for k in s:
        if k == 'zero':
            ans.append('0')
        elif k == 'one':
            ans.append('1')
        elif k == 'two':
            ans.append('2')
        elif k == 'three':
            ans.append('3')
        elif k == 'four':
            ans.append('4')
        elif k == 'five':
            ans.append('5')
        elif k == 'six':
            ans.append('6')
        elif k == 'seven':
            ans.append('7')
        elif k == 'eight':
            ans.append('8')
        elif k == 'nine':
            ans.append('9')
else:
    print('Wrong input')

bac = str(ans[0]) + str(ans[1]) + str(ans[2])
if bac in kolchos:
    print(bac)
else:
    ples = int(bac)
    shag_plus = 0
    menus = int(bac)
    shag_mines = 0
    while ples not in kolchos:
        ples += 1
        shag_plus += 1
    while menus not in kolchos:
        menus -= 1
        shag_mines += 1
    if shag_mines < shag_plus:
        print(menus)
    else:
        print(ples)



